The terms that comes to mind for me is 'a convenient happenstance in your case'. Maybe like changing out your transmission to one with overdrive with the thought to extend your engine life, and discovering you now get better fuel mileage. That's the best analogy I can bring to mind at the moment -
It is true that installing wine will get the 32 bit libraries installed on a 64 Bit Linux distribution, but its a by-product of the process, not its intent.
The 'real reason' that happens to be the case is #10 on this page:http://wiki.winehq.org/Debunking_Wine_Myths
"THUS" - I stand with my contention that the 'right thing to do' in most cases is to simply install the ia32 libraries, as you get no benefit from Wine unless you plan to use the machine to run Windows apps.
Good Luck with LAMPP.